This is a much wanted feature, and I have long term plans to solve this issue together with a lot of other issues using a distributed data store (file system, d

This is a much wanted feature, and I have long term plans to solve this issue together with a lot of other issues using a distributed data store (file system, database, whatever you want to call it). See https://toktok.github.io/roadmap#distributed-file-system https://toktok.github.io/roadmap#distributed-file-system (milestone 9). More realistically, i.e. in the nearer future, milestone 4 (https://toktok.github.io/roadmap#optimisations-for-mobile https://toktok.github.io/roadmap#optimisations-for-mobile) covers a simple multi-device feature. GrayHatter has implemented a prototype and will deliver a design document for the full implementation likely by the end of Q4. It includes profile and contact sync as well as message history sync. If we follow the intended timeline, that feature would likely land somewhere in 2017Q1. uTox and qTox have preliminary support for the prototype. You and everybody else are invited to review the proposal when it comes out. Be sure to follow the issues on https://github.com/TokTok/c-toxcore/issues https://github.com/TokTok/c-toxcore/issues. You are also invited to join #toktok on Freenode to bounce ideas around. Offline messaging will be partially solved by message log sync, as mentioned in milestone 4. The idea is that if you have a desktop computer at home, you could sync the message from your phone to it, and the desktop computer will deliver the message to your friend when they come online. It could be that your desktop syncs with their desktop at some point, and later their desktop syncs with their phone which is the actual delivery. In any case, this solution requires at least one of your and their devices to be online at one point. So far, we have shied away from storing large amounts of data in the network itself. I think the described solutions are sufficient for a large group of users. Federated (email-like) server-based (still distributed, just not p2p) solutions could be used for the remainder.